Sci-fi 'Riddick' pits Vin Diesel vs. the Mud Demons

05:00 AM, Jan 13, 2014

Written Byby Brian Truitt, USA TODAY

Poor Vin Diesel.

Not only does his cosmic convict Riddick have to deal with two groups of bounty hunters but he also needs to survive an alien planet full of hostile, snarling Mud Demons in the sci-fi movie Riddick, out on Blu-ray and DVD Tuesday.

And they’re really nasty beasts, says visual-effects supervisor Gunnar Hansen in one of the sequences on the Blu-ray bonus features that shows how director David Twohy and his team animated the Mud Demons. The creepy, computer-generated creatures were added later on in post-production, while practical effects such as crew members tossing muddy “goopage” around the stage  were used to help Diesel act as if in peril from oncoming monsters.

“All the dynamics of the mud are being analyzed and being applied to the CG models, and the Mud Demons are living breathing creatures in the CG world,” Hansen says. “We certainly wanted to impart the sense of danger that they pose to Riddick and the mercs in the final battle.”

Other Blu-ray extras include a “Meet the Mercs” featurette focusing on characters played by Katee Sackhoff, Dave Bautista, Bokeem Woodbine and others, a look at Twohy’s vision for the sci-fi franchise and Diesel’s passion for playing the Riddick character, and a motion-comic prequel set after the events of 2004’s The Chronicles of Riddick.